1. Field of the Invention
The present invention generally relates to telecommunication systems, and more particularly to key telephone systems and trading turrets.
2. Description of the Related Art
A trading turret system is a specialized telephony switching system that allows a relatively small number of users to access a large number of external lines and provides enhanced communication features such as hoot-n-holler, push-to-talk, intercom, video and large-scale conferencing. These features are often utilized in the financial industry such as trading floor environments, as well as security/law enforcement, utilities, healthcare, and customer support (e.g., contact centers) environments.
Users interface with a turret switching system through a trading turret device, which can be implemented in dedicated hardware (sometimes referred to as a “hard” turret) or in a general-purpose computer (sometimes referred to as a “soft” turret). A hard-turret is a phone-like desktop device with multiple handsets, speakers and buttons. A soft-turret is a software application that runs on a trader's desktop personal computer (PC) or on a mobile computer such as a PDA (Personal Digital Assistant). A soft-turret application may be controlled using the native control interface that the computer provides such as a touch screen, stylus, click wheel, or mouse and keyboard. In addition to rendering a graphical image of the turret on the PC screen, the soft-turret application may also provide voice, instant messaging and presence features.
With the introduction of Session Initiation Protocol (“SIP”) based architectures, new features and interoperability with a wide variety of SIP enabled devices is possible. SIP is an application-layer control (i.e., signaling) protocol for creating, modifying, and terminating sessions such as Internet telephony calls with one or more participants and is defined in RFC-3261, “SIP: Session Initiation Protocol”. SIP has been used in typical IP based networks as the predominant way of signaling between stations and telephony systems and as the trunking protocol between telephony systems. SIP also can be used in conjunction with other protocols such as Session Description Protocol “SDP” and Real-Time Protocol “RTP” to provide communications services.
With the advent of Voice over Internet Protocol (“VoIP”), VoIP turret devices have moved from a fixed environment of dedicated voice communications trading resources to a more virtualized and remotely accessible trading environment across multiple sites. This virtual environment allows trader mobility (e.g., to roam across multiple trading floors), and disaster recovery planning and resources (e.g., remote access to their private wires) to be shared dynamically, when and where required, across a global corporate enterprise.
FIG. 1 shows an overview of a previous generation soft-turret product. This system makes us of an external hardware media bridge 102 and a hard-turret 104 for one soft-turret instance to operate. Hard-turret 104 typically includes two handsets, commonly referred to as a Left Handset “LHS” and a Right Handset “RHS” and multiple speaker devices. This allows a trader to have many independent voice conversations simultaneously. A soft-turret 106 is typically connected to a turret switching system 112 through a network such as the Internet 114 and is accompanied by a single phone device for voice delivery. Thus, soft-turret users have a single handset only.
To accommodate for this, a typical soft-turret product makes use of the external media bridge 102 to bridge the LHS to RHS so that one channel is used to connect to the private wire network 110 and the other channel is used to connect a public-switched-telephone-network or PSTN phone 108 over a PSTN network 116. This solution is costly, however, because it requires an external piece of hardware and requires a hard-turret to be dedicated to the remote trader.
Typical soft phones have other practical limitations. For example, a soft-phone runs on a PC and is typically connected to an organization's private branch exchange (PBX) and makes use of VoIP to communicate with the PBX. In such configurations, the soft-phone can exchange signaling (e.g., SIP) and media (e.g., RTP) with the PBX but does not have a dedicated data channel with the PBX for rendering a display to the user. Soft phones are typically also not capable of delivering multiple conversations (such as multiple handsets and speakers as is the case in turrets) simultaneously.
Another factor that must be taken into consideration when dealing with trader communications is voice quality. Voice quality requirements (such as voice cut-through times) in a trading environment are significantly more stringent than in an enterprise PBX environment. For instance, as soon as a trader seizes a private wire, voice communications must be established immediately (e.g., <50 ms) such that a single spoken syllable from the trader is not dropped.
Another bottleneck in existing trader systems is their computing systems. A trader's personal computer may be running many voice applications simultaneously such as Voice and Instant Messaging clients, Web browsers with voice enabled Web pages, etc. In addition, the personal computer's operating system is usually non-real time, which means it is not capable of switching tasks in real time in order to preempt low priority tasks to allow applications delivering voice media to run. Sending the voice to trader's PSTN (Public Switched Telephone Network) phone line thus presents contention issues.